Help! New Finish Sand-Through

[Philip Secrist]

I sprayed my archtop with what I thought was enough nitro finish, let it cure for 3 weeks, level sanded it, and buffed it out with medium Menzerna dry polish. However, looking closely I discovered that I could still see some tiny shiny (shrinkage) spots especially in the re-curve area on the back so I tried to level them out with 600 grit wet sand paper. It didn't seem like I sanded that much but I am starting to sand through and there are still some shiny spots in the location as well as elsewhere. So, I am thinking that the finish just wasn't thick enough to begin with. Would there be a problem with spraying more coats of nitro and repeating the process, even after having buffed it out with medium Menzerna polish? I want the finish to be right. Since the new finish has been buffed do I need to sand it with 320 grit or something to rough it up before applying more nitro finish?

[Mark Swanson]

Wipe it down with naptha, make sure it's clean and you can spray more on there.

[Michael Lewis]

Finish dried 3 weeks, I would probably spray it lightly with thinner a couple minutes before spraying more lacquer, this helps 'open' the surface to the new lacquer. It's not necessary if you don't sand through again but helps, especially on older lacquer.